| Strong Forge & Fabrication, LLC Milling, Bending, Welding, Finishing | Batavia, NY | MillingBendingWeldingFinishing | - |
| Summit Machine Company Milling, Turning, Welding, Finishing · ISO 9001 | Alverton, PA | MillingTurningWeldingFinishing | ISO 9001 |
| Summit Machining Co., Ltd Milling, Turning, Welding, Stamping, Casting, Finishing | Mogadore, OH | MillingTurningWeldingStampingCastingFinishing | - |
| Summit Products Inc Milling, Bending, Welding, Finishing | Altoona, IA | MillingBendingWeldingFinishing | - |
| Sunspot Solutions LLC Welding | Lyons, IN | Welding | - |
| Superior Pipe Fabricators Welding | Los Angeles, CA | Welding | - |
| Superior Steel Fabrication Welding, Finishing · ISO 9001, AS9100 | Eugene, OR | WeldingFinishing | ISO 9001, AS9100 |
| Superior Technology Inc Milling, Turning, Swiss, Welding, Grinding, Finishing, Assembly · ISO 9001 | Rochester, NY | MillingTurningSwissWeldingGrindingFinishingAssembly | ISO 9001 |
| Support Equipment Inc Milling, Turning, Welding, EDM, Finishing, Assembly · ISO 9001, AS9100, ITAR | Escondido, CA | MillingTurningWeldingEDMFinishingAssembly | ISO 9001, AS9100, ITAR |
| Surfix Inc Milling, Bending, Welding | Palm Bay, FL | MillingBendingWelding | - |
| Susquehanna Metal Work, LLC Milling, Bending, Welding, Stamping | Columbia, PA | MillingBendingWeldingStamping | - |
| Swan Island Sheet Metal Works Turning, Bending, Laser, Welding | Portland, OR | TurningBendingLaserWelding | - |
| Swanton Welding & Machining Co Inc Milling, Laser, Bending, Welding, Finishing, Assembly | Swanton, OH | MillingLaserBendingWeldingFinishingAssembly | - |
| Swift Industries Inc Milling, Laser, Punching, Bending, Welding, Stamping, Grinding, Finishing, Assembly · ISO 9001 | Suwanee, GA | MillingLaserPunchingBendingWeldingStampingGrindingFinishingAssembly | ISO 9001 |
| Swiss Technologies Inc. Milling, Turning, Welding, Stamping · ISO 9001 | Knoxville, TN | MillingTurningWeldingStamping | ISO 9001 |
| Swiss Wire EDM Milling, Turning, Welding, EDM · ISO 9001, ITAR, NADCAP | Costa Mesa, CA | MillingTurningWeldingEDM | ISO 9001, ITAR, NADCAP |
| T & D Specialties Milling, Turning, Swiss, Welding, Finishing · ISO 9001 | Oxford, MA | MillingTurningSwissWeldingFinishing | ISO 9001 |
| T-Tygart Industries, Inc Milling, Turning, Bending, Welding, Grinding | Carmichaels, PA | MillingTurningBendingWeldingGrinding | - |
| Tabet Manufacturing Co Inc Milling, Turning, Laser, Waterjet, Punching, Bending, Welding, Finishing, Assembly · ISO 9001, ITAR | Norfolk, VA | MillingTurningLaserWaterjetPunchingBendingWeldingFinishingAssembly | ISO 9001, ITAR |
| Tag Team Manufacturing Turning, Welding, Finishing · ISO 9001 | Parker, CO | TurningWeldingFinishing | ISO 9001 |
| Tahl Inc Milling, Turning, Welding, EDM, Grinding, Finishing · ISO 9001, ITAR, CMMC | Tucson, AZ | MillingTurningWeldingEDMGrindingFinishing | ISO 9001, ITAR, CMMC |
| Tam Metal Products Punching, Welding, Stamping, Finishing · NADCAP | Mahwah, NJ | PunchingWeldingStampingFinishing | NADCAP |
| Tampa Bay Machining Milling, Turning, Welding, EDM · ISO 9001, AS9100, ITAR | Tampa, FL | MillingTurningWeldingEDM | ISO 9001, AS9100, ITAR |
| TBC Metalworks Bending, Laser, Welding | Green Bay, WI | BendingLaserWelding | - |
| TCMS Inc Milling, Turning, Welding | Oklahoma City, OK | MillingTurningWelding | - |
| Tech-Weld Inc Laser, Welding · NADCAP | Sycamore, IL | LaserWelding | NADCAP |
| Tel-X Corporation Milling, Turning, Laser, Welding, Stamping, EDM, Finishing · ISO 9001, IATF 16949 | Garden City, MI | MillingTurningLaserWeldingStampingEDMFinishing | ISO 9001, IATF 16949 |
| Tem Inc Milling, Laser, Welding, Stamping, EDM, Assembly · ISO 9001, AS9100 | Buxton, ME | MillingLaserWeldingStampingEDMAssembly | ISO 9001, AS9100 |
| Tennessee Tool & Engineering Inc Welding, Casting, Assembly · ISO 9001 | Oak Ridge, TN | WeldingCastingAssembly | ISO 9001 |
| Texas Metal Specialty Co Laser, Welding, Waterjet | Houston, TX | LaserWeldingWaterjet | - |
| Texas Sheet Metal Bending, Welding | San Antonio, TX | BendingWelding | - |
| The Bennu Group Inc Milling, Turning, Waterjet, Welding, Finishing · ISO 9001 | South Holland, IL | MillingTurningWaterjetWeldingFinishing | ISO 9001 |
| The Champ Company Welding, Assembly | Campbell, CA | WeldingAssembly | - |
| The Charles Schillinger Co., Inc Turning, Welding, Stamping · ISO 9001 | Bensalem, PA | TurningWeldingStamping | ISO 9001 |
| The Inventors Shop, L.L.C Milling, Turning, Laser, Waterjet, Punching, Bending, Welding, Stamping, Assembly · ISO 9001, ITAR | Cinnaminson, NJ | MillingTurningLaserWaterjetPunchingBendingWeldingStampingAssembly | ISO 9001, ITAR |
| The Rembar Company LLC Milling, Turning, Welding, EDM, Grinding | Dobbs Ferry, NY | MillingTurningWeldingEDMGrinding | - |
| The Toolroom, Inc Milling, Punching, Welding, EDM | Owensville, MO | MillingPunchingWeldingEDM | - |
| Thermo-Craft Engineering Corp Milling, Turning, Waterjet, Punching, Bending, Welding, Grinding, Assembly | Lynn, MA | MillingTurningWaterjetPunchingBendingWeldingGrindingAssembly | - |
| Think Variant Inc Milling, Turning, Laser, Bending, Welding, Casting, Metal AM | Phoenix, NY | MillingTurningLaserBendingWeldingCastingMetal AM | - |
| Third Reef Machining and Engineering Ltd. Co Milling, Bending, Welding, Finishing | Cottonwood Heights, UT | MillingBendingWeldingFinishing | - |
| Thompson & Smith Industries LLC Milling, Turning, Welding, EDM, Grinding | Tullahoma, TN | MillingTurningWeldingEDMGrinding | - |
| Thompson-Mathis Metal Mfg. Bending, Welding | Dallas, TX | BendingWelding | - |
| THR Machinery Milling, Turning, Bending, Welding | Allons, TN | MillingTurningBendingWelding | - |
| Tiger Precision Machining Milling, Turning, Welding, Finishing | Lodi, CA | MillingTurningWeldingFinishing | - |
| Tis Aerospace LLC Milling, Turning, Waterjet, Punching, Welding, Stamping, Assembly | Cinnaminson, NJ | MillingTurningWaterjetPunchingWeldingStampingAssembly | - |
| TMS Inc Milling, Laser, Punching, Bending, Welding, Grinding, Finishing, Assembly | New Berlin, WI | MillingLaserPunchingBendingWeldingGrindingFinishingAssembly | - |
| Toledo Metal Spinning Company Milling, Bending, Laser, Welding, Stamping · ISO 9001 | Toledo, OH | MillingBendingLaserWeldingStamping | ISO 9001 |
| Tolerance Tool & Engineering Milling, Turning, Welding · ISO 9001, ITAR | Detroit, MI | MillingTurningWelding | ISO 9001, ITAR |
| Tompkins Products, Inc Milling, Welding, Grinding, Finishing · IATF 16949 | Detroit, MI | MillingWeldingGrindingFinishing | IATF 16949 |
| Toolco Inc Milling, Turning, Welding, Stamping, EDM, Grinding | Owensboro, KY | MillingTurningWeldingStampingEDMGrinding | - |